I brazed it Andy. Didn't take any pics but when/if I do the rest that have shown up I'll get some.
Not sure what to do about the paint, think I'd rather take it to someone decent than get this bloke to redo it. But I'm aware that with the money I'm sinking into this I could just buy a decent frame.
Disappointed with how it's gone so far, so I'm going to leave it for a while and then come back to it.
It sounds as if some contamination has occurred between the sand blasting and the painting which they (the powdercoaters) haven't spotted or removed. Could be something as simple as oily fingerprints while you were brazing and smoothing off.